For almost every shaving operation it is known that hair is more easily cut when it is heated. Additionally, it is known that heating the skin surface which is being shaved also helps soothe and comfort the skin. These advantages which are realized when heat is applied to the hair and surface to be shaved are important to any shaving process.
In a typical blade shaving process, the cutting edge the a blade is drawn across the skin surface to cut hair that is in the path of the blade. When a safety razor is used, this process normally involves first wetting the surface to be shaved with warm water. A hair softening agent, such as shaving cream or lotion, may also be applied on the surface. Such a procedure is called a "wet" shave and is to be distinguished from a "dry" shave where no water is used, and no hair softening agents are applied. Despite several apparent conveniences a "dry" shave can have some disadvantages. The main drawback to "dry" shaving is that razor blades cannot be used repeatedly, or for extended "dry" shaving operations, due to the rapid deterioration of their cutting edges when the blades are used without any hair softening agents. Furthermore, as the cutting edge deteriorates, the blade becomes more and more useless and the possibility of extreme irritation to the skin is increased. The present invention, however, recognizes that many of the problems normally associated with "dry" shaving can be avoided if the hair and skin surface to be shaved are properly heated.
Through the years many shaving systems and procedures have been proposed for the purpose of providing greater shaving comfort. For instance, the application of hot water or hot shaving cream to a skin surface prior to shaving is known to provide greater comfort during the shaving operation. Unfortunately, hot water is not always readily available. Even when hot water is available, it will rapidly cool down after it is applied to the skin. Furthermore, if shaving cream is used, it may be cold and, aside from its lubricating effect this will tend to reduce the advantage gained from the hot water. On the other hand, hot shaving cream may be impractical. There must be some means for heating the shaving cream and, even if a hot shaving cream dispenser is available, it is often inconvenient to heat the shaving cream prior to shaving. In any case, shaving cream is disfavored by many because it can cover an area from view, such as the edge of a beard, which could then be mistakenly shaven. As recognized by the present invention, many of these disadvantages encountered in a "wet" shaving system can be overcome if a "dry" shaving system is used.
As implied above, to be comfortable, a "dry" shaving system must efficiently employ the use of heat. Shavers with heated blades that conduct heat directly from the blade to the hair prior to shaving have been proposed for a "dry" shaving operation. Heated blades, however, are problematic because of the potential for skin burns which can be caused when the heated blade contacts the skin. Additionally, heated blades are relatively inefficient because the blade does not efficiently conduct heat to the hair. This problem is due to insufficient heat transfer and is caused by several factors. These factors include the area of contact between the blade and the hair, the temperature difference between the blade and the hair, and the amount of time the blade contacts the hair. When using only a heated blade the area of contact between the cutting edge of the blade and the hair shaft is extremely limited due to the fineness of both the hair and the edge of the blade. To overcome this disadvantage, the blade temperature should be raised. There is a limit, however, since the blade temperature must be maintained below the temperature at which skin will blister or burn. Time is thus the only remaining process variable. It happens, however, that the time which is required to effectively heat hair with only a heated blade renders their use effectively impractical. The present invention recognizes that other ways for heating the hair and skin surface need to be provided.
In light of the above, it is an object of the present invention to provide a shaving system which is able to achieve a comfortable "dry" shave without requiring the application of a heated substance such as hot water or heated shaving cream to the area to be shaved. It is another object of the present invention to heat hair and shave the heated hair before it cools. It is yet another object of the present invention to provide a thermally enhanced shaver which will heat an area of skin without causing burns. It is still another object of the present invention to provide a thermally enhanced shaver which uses hot air to heat the blades in addition to the area to be shaved. Yet another object of the present invention is to provide a thermally enhanced shaver which is relatively easy to manufacture and which is comparatively cost effective.